Why where the Teleri Ships Irreplaceable?

[akhtene]

To TarElendil: yes, I agree that Feanor's passion for the stones was greater, but still I think that the Telleri's pride and love for their ships was not less, the more so that they were the creation the people, not a single craftsman, and were admired by everyone of them.
About Feanor and Silmarils

He never said that the valar couldnt have the silmarils for the trees.

He probably couldn't say exactly this to Valar. What he said was:

This thing I will not do of free will. But if the Valar will constrain me, then shall I know indeed that Melkor is if their kindred

To me it sounds like giving in to power, not a free-will agreement